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E-mail will be much more usable the day when
the receiving apparatus immediately emits a
beep or blinking light signalling the arrival of
a message. The messaging apparatus should be
equally cheap to own as a telephone that rarely
rings. We are still some distance from being able
to send important messages to many recipients
by e-mail only. But the trend is pointing in that
direction. And a transmitter and receiver of e-
mail will not be a PC only. It will be built into
telephones or other future “popular boxes”, that
we have not yet seen, but which will creatively
be made usual in the future world. Many such
boxes will be gadgets with remotely controlled
functions, etc.

Wireless or Wired Somehow

The actual reason for the name Internet is that
the network may employ various carrier media
of many different kinds interconnected for the
transportation of information.

Further, Internet-technology implies mechanisms
for optimized mixing of different transport re-
quirements. Urgent messages get there fast while
less urgent traffic may be transported more cheap-
ly using otherwise idle periods. Traffic types are
more or less error prone. Particularly important
traffic needs precedence – e.g. for resolving
problems in the network itself, and so on.

Characteristics such as error density, urgency,
and precedence are measurable quantities to be
specified, and to be met accordingly. Internet
technology lets different requirements be met
automatically by the available network capabilities.

In particular this enables many carrier media of
rather different capabilities to co-operate in the
transport such that each medium is exploited to
its best ability. Prevailing media now are leased
lines capable of specific bit transfer rates – num-
ber of pulses per second. Various standard band-
widths (pulses per second) are available. Several
other carrier media are important and will be
used increasingly. Local area networks prevail
within buildings and geographically limited cor-
porate sites. Radio computer networking of vari-
ous kinds is evolving further.

Satellites have many exciting possibilities. The
same is true of cable networks originally built
for broadcasting television. These are probably
best suited for rural and urban areas respectively,
and have great potential for being exploited further.

The background for the name Internet is net of
interconnected nets. The individual transport
networks are operated separately as mask-shaped
nets of leased lines, packet radio nets, packet
satellite nets, and so on. Each of these media
transports packets in ways best suited for each

type of net. The individual nets are connected

into one network (of nets) called Internet. Gate-

way computers make the interconnection. They

convert the information on its way to the next

net into a format suitable for appropriate han-

dling there.

The basic development of Internet-technology

took place in the period 1969 – 1980. It com-

prised understanding the problems and the possi-

bilities, creating and testing the technical meth-

ods and defining the results as standards that

were open and available for use by anyone.

The main result of this development is that dif-

ferent computers can now co-operate and ex-

change all types of information. Further, the

Teleprinter, (“Teletype”,

“Telex machine”) built for the

international Telex network

was extensively used as

computer terminals

Packet

radio

net

Local

area

net

Packet

satellite

net

Net of

leased

lines

Local

area

net

Local

area

net

G

G

G

G

G

G

G

Host A Host B

The Internet is a network of

nets interconnected by gateway

computers. Nets may be of

different types. From one host

computer to another

information travels in packets

along routes which may

change with network “shape”

and traffic load. The Internet

Protocol (IP) helps navigate

through the network. The

Transport Control Protocol

(TCP) helps ensure that a

message transported

piecemeal as a number of

packets gets properly

re-assembled